Billionaires and politicians gathering in Switzerland this week will come under pressure to tackle rising inequality after a study found that – on current trends – by next year, 1% of the world’s population will own more wealth than the other 99%.

Ahead of this week’s annual meeting of the World Economic Forum in the ski resort of Davos, the anti-poverty charity Oxfam said it would use its high-profile role at the gathering to demand urgent action to narrow the gap between rich and poor.

Oxfam added that on current trends the richest 1% would own more than 50% of the world’s wealth by 2016.

Pope Francis and the IMF managing director Christine Lagarde have been among those warning that rising inequality will damage the world economy if left unchecked, while the theme of Thomas Piketty’s best-selling book Capital was the drift back towards late 19th century levels of wealth concentration.

Barack Obama’s penultimate State of the Union address on Tuesday is also expected to be dominated by the issue of income inequality.

He will propose a redistributive tax plan to extract more than $300bn (£200bn) in extra taxes from the 1% of rich earners in order to fund benefits specifically targeted at working families.